<?php
use yii\widgets\ActiveForm;
?>
<div class="row">
    <div class="col-md-4 col-md-offset-4 col-sm-6 col-sm-offset-3">
        <?php
        $form = ActiveForm::begin([
            'id' => 'category-form',
            'options' => ['class' => 'sky-form'],
        ])
        ?>
            <div class="reg-header">
                <h2>Login to your account</h2>
            </div>

            <div class="input-group margin-bottom-20">
                <span class="input-group-addon"><i class="fa fa-user"></i></span>
                <input type="text" class="form-control" placeholder="Username" name="username">
            </div>
            <div class="input-group margin-bottom-20">
                <span class="input-group-addon"><i class="fa fa-lock"></i></span>
                <input type="password" class="form-control" placeholder="Password" name="password">
            </div>

            <div class="row">
                <div class="col-md-6 checkbox">
                    <label><input type="checkbox"> Stay signed in</label>
                </div>
                <div class="col-md-6">
                    <button type="submit" class="btn-u pull-right">Login</button>
                </div>
            </div>

            <hr>

            <h4>Forget your Password ?</h4>
            <p>no worries, <a href="#" class="color-green">click here</a> to reset your password.</p>
        <?php ActiveForm::end() ?>
    </div>
</div>